Effets des nanoparticules manufacturées sur les cellules pulmonaires humaines

La détection et la caractérisation des nanoparticules manufacturées (NPM) est l’une des premières étapes pour contrôler et diminuer leurs risques potentiels sur la santé humaine et l’environnement. Différents systèmes d’échantillonnage dans l’air existent pour l’évaluation d’une exposition aux NPM. Cependant, ils ne mesurent pas le risque potentiel de cette exposition à la santé humaine ni les mécanismes cellulaires qui en seraient responsables. Nos objectifs de recherche sont 1) Évaluer les effets de différents types de nanoparticules sur des cellules pulmonaires humaines et 2) Identifier de nouveaux mécanismes intracellulaires activés lors de l’exposition à divers types de NPM. Méthodologie: La lignée de cellules A549 a été utilisée. Trois types de NPM ont été étudiés (différentes concentrations et temps d’exposition): les nanoparticules de dioxyde de titane de type anatase (TiO2), les nanotubes de carbone simple paroi (NTCSP) et les nanoparticules de noir de carbone (NC). La viabilité cellulaire a été mesurée par le test MTS, le test PrestoBlue et le test d’exclusion du bleu de Trypan (uniquement pour les NTCSP). La mesure du stress oxydatif a été déterminée par la mesure des dérivés réactifs de l’oxygène (ROS) en utilisant l’essai DCFH-DA. L’activation d’une réponse anti-oxydative a été déterminée par la mesure de la forme réduite (GSH) et oxydée (GSSG) du glutathion, ainsi que du ratio GSH/GSSG (seulement avec NTCSP et TiO2). Résultats: Les trois nanoparticules ne semblent pas être toxiques pour les cellules A549 car il y a une diminution significative mais minime de la viabilité cellulaire. Cependant, elles induisent une augmentation du contenu intracellulaire en ROS qui est à la fois dépendante du temps et de la concentration. Aucun changement dans les concentrations de GSH et GSSG n’a été observé. En conclusion, nos données indiquent que la mesure de la viabilité n’est pas un critère suffisant pour conclure à la toxicité des NPM. La production de ROS est un critère intéressant, cependant il faudra démontrer l’activation de systèmes anti-oxydatifs pour expliquer l’absence de mortalité cellulaire suite à l’exposition aux NPM.

Mémoire de la disparition : "Récits d’Ellis Island", l’album

Compte rendu de l'album « Récits d'Ellis Island : histoires d'errance et d'espoir » (POL, 1994).

Les isoloirs

Choco n’est pas un type standard. Voilà ce que répète le patron de La Caboose depuis deux ans. Pour commencer, Choco est immense. Plus de deux mètres. Cent vingt kilos de muscles. Ensuite, Choco est le seul homme noir du bar. Ni crips, ni blood, ni motard, ni mafieux, seulement noir. Aux curieux, Choco raconte qu’il n’a pas besoin d’affiliations pour faire sa place, qu’il travaille en solo, en artiste. « C’est que j’en suis un, moi, un artiste. » À ce propos, personne ne le contredit. Personne n’oserait.

Valoración del costo de los recursos propios de las empresas. caso particular: empresas de servicios a la persona en Francia

El WACC o Coste Medio Ponderado de Capital es la tasa a la que se deben descontar los flujos para evaluar un proyecto o empresa. Para calcular esta tasa es necesario determinar el costo de la deuda y el costo de los recursos propios de la compañía; el costo de la deuda es la tasa actual del mercado que la empresa está pagando por su deuda, sin embargo el costo de los recursos propios podría ser difícil y más complejo de estimar ya que no existe un costo explícito. En este trabajo se presenta un panorama de las teorías propuestas a lo largo de la historia para calcular el costo de los recursos propios. Como caso particular, se estimará el costo de los recursos propios sin apalancamiento financiero de seis empresas francesas que no cotizan en bolsa y pertenecientes al sector de Servicios a la Persona (SAP). Para lograr lo anterior, se utilizará el Proceso de Análisis Jerárquico (AHP) y el Modelo de Valoración del Precio de los Activos Financieros (CAPM) con base en lo presentado por Martha Pachón (2013) en “Modelo alternativo para calcular el costo de los recursos propios”.

Genome expansion and gene loss in powdery mildew fungi reveal tradeoffs in extreme parasitism

Powdery mildews are phytopathogens whose growth and reproduction are entirely dependent on living plant cells. The molecular basis of this life-style, obligate biotrophy, remains unknown. We present the genome analysis of barley powdery mildew, Blumeria graminis f.sp. hordei (Blumeria), as well as a comparison with the analysis of two powdery mildews pathogenic on dicotyledonous plants. These genomes display massive retrotransposon proliferation, genome-size expansion, and gene losses. The missing genes encode enzymes of primary and secondary metabolism, carbohydrate-active enzymes, and transporters, probably reflecting their redundancy in an exclusively biotrophic life-style. Among the 248 candidate effectors of pathogenesis identified in the Blumeria genome, very few (less than 10) define a core set conserved in all three mildews, suggesting thatmost effectors represent species-specific adaptations.

Tropical palaeoclimates at the Last Glacial Maximum: comparison of Palaeoclimate Modeling Intercomparison Project (PMIP)simulations and paleodata.

Seventeen simulations of the Last Glacial Maximum (LGM) climate have been performed using atmospheric general circulation models (AGCM) in the framework of the Paleoclimate Modeling Intercomparison Project (PMIP). These simulations use the boundary conditions for CO2, insolation and ice-sheets; surface temperatures (SSTs) are either (a) prescribed using CLIMAP data set (eight models) or (b) computed by coupling the AGCM with a slab ocean (nine models). The present-day (PD) tropical climate is correctly depicted by all the models, except the coarser resolution models, and the simulated geographical distribution of annual mean temperature is in good agreement with climatology. Tropical cooling at the LGM is less than at middle and high latitudes, but greatly exceeds the PD temperature variability. The LGM simulations with prescribed SSTs underestimate the observed temperature changes except over equatorial Africa where the models produce a temperature decrease consistent with the data. Our results confirm previous analyses showing that CLIMAP (1981) SSTs only produce a weak terrestrial cooling. When SSTs are computed, the models depict a cooling over the Pacific and Indian oceans in contrast with CLIMAP and most models produce cooler temperatures over land. Moreover four of the nine simulations, produce a cooling in good agreement with terrestrial data. Two of these model results over ocean are consistent with new SST reconstructions whereas two models simulate a homogeneous cooling. Finally, the LGM aridity inferred for most of the tropics from the data, is globally reproduced by the models with a strong underestimation for models using computed SSTs.

Tropical climates at the Last Glacial Maximum: a new synthesis of terrestrial palaeoclimate data. I. Vegetation, lake-levels and geochemistry.

Palaeodata in synthesis form are needed as benchmarks for the Palaeoclimate Modelling Intercomparison Project (PMIP). Advances since the last synthesis of terrestrial palaeodata from the last glacial maximum (LGM) call for a new evaluation, especially of data from the tropics. Here pollen, plant-macrofossil, lake-level, noble gas (from groundwater) and δ18O (from speleothems) data are compiled for 18±2 ka (14C), 32 °N–33 °S. The reliability of the data was evaluated using explicit criteria and some types of data were re-analysed using consistent methods in order to derive a set of mutually consistent palaeoclimate estimates of mean temperature of the coldest month (MTCO), mean annual temperature (MAT), plant available moisture (PAM) and runoff (P-E). Cold-month temperature (MAT) anomalies from plant data range from −1 to −2 K near sea level in Indonesia and the S Pacific, through −6 to −8 K at many high-elevation sites to −8 to −15 K in S China and the SE USA. MAT anomalies from groundwater or speleothems seem more uniform (−4 to −6 K), but the data are as yet sparse; a clear divergence between MAT and cold-month estimates from the same region is seen only in the SE USA, where cold-air advection is expected to have enhanced cooling in winter. Regression of all cold-month anomalies against site elevation yielded an estimated average cooling of −2.5 to −3 K at modern sea level, increasing to ≈−6 K by 3000 m. However, Neotropical sites showed larger than the average sea-level cooling (−5 to −6 K) and a non-significant elevation effect, whereas W and S Pacific sites showed much less sea-level cooling (−1 K) and a stronger elevation effect. These findings support the inference that tropical sea-surface temperatures (SSTs) were lower than the CLIMAP estimates, but they limit the plausible average tropical sea-surface cooling, and they support the existence of CLIMAP-like geographic patterns in SST anomalies. Trends of PAM and lake levels indicate wet LGM conditions in the W USA, and at the highest elevations, with generally dry conditions elsewhere. These results suggest a colder-than-present ocean surface producing a weaker hydrological cycle, more arid continents, and arguably steeper-than-present terrestrial lapse rates. Such linkages are supported by recent observations on freezing-level height and tropical SSTs; moreover, simulations of “greenhouse” and LGM climates point to several possible feedback processes by which low-level temperature anomalies might be amplified aloft.

Regurgitated bodies: presenting and representing trauma in 'The Act of Killing'

Focusing on The Act of Killing, this chapter examines how an “ethics of realism” operates on three key cinematic arenas: genre, authorship and spectatorship. As far as genre is concerned, the film’s realist commitment emerges from where it is least expected, namely from Hollywood genres, such as the musical, the film noir and the western, which are used as documentary, that is to say, as a fantasy realm where perpetrators can confess to their crimes without restraints or fear of punishment, but which nonetheless retains the evidentiary weight of the audiovisual medium. Authorship, in turn, translates as Oppenheimer’s unmistakable auteur signature through his role of self-confessed “infiltrator” who disguises as a sympathiser of the criminals in order to gain first-hand access to the full picture of their acts. One of them, the protagonist Anwar Congo, is clearly affected by post-traumatic stress disorder, and his repetitive reliving of his killings is made to flare up in front of the camera so as to bring back the dead to the present time in their material reality, through his own body, including a harrowing scene of the actor’s unpredictable and uncontrollable retching as he re-enacts the killing of his victims through strangulation. Finally, in the realm of spectatorship, the usual process of illusionistic identification on the part of the spectator is turned onto its head by means of disguising these criminals as amateur filmmakers, led to shoot, act within, and then watch their own film within the film so as to force them to experience beyond any illusion the suffering they had caused.

A experiência ficcional de Gérard Aké Loba: utopia e construção da identidade pós-colonial

A experiência ficcional de Gérard Aké Loba — Kocoumbo, l’étudiant noir(1960), Les fils de Kouretcha (1970), Les dépossédés (1973) e Le sas des parvenus(1990), ancorada na dinâmica de culturas, no respeito e na honorabilidade do Eu e do Outro, centra-se na problemática da utopia e da construção da identidade pós-colonial. Considerando que a Literatura, enquanto sistema semiótico de produção e recepção de textos, se encontra vinculada a uma visão do mundo, iremos ver como nela se manifestam as relações entre o Ocidente (Europeu) e as regiões da África francófona (Costa do Marfim) no percurso das metamorfoses que conduzem ao Pós-Colonialismo. Procuraremos, de igual modo, problematizar a utopia, e também a distopia, comungando da proposta de Éric Aunoble2, para quem estas questões deverão ser compreendidas na sua relação com o tempo e com a historicidade presente por tentarem responder “aux attentes de leurs temps”.

Stendhal pensador: o conceito feito narrativa

Il s'agit ici d'ébaucher quelques aspects de la pensée - dans son sens conceptuel et systématique - de Stendhal, son discours refléxive, exprès dans l'style narrative à travers le roman, surtout dans Le rouge et le Noir.

Cheira bem pode fazer mal: a configuração de O perfume como romance policial

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Romance Negro de Rubem Fonseca: conto fantástico ou narrativa policial?

Este artigo analisa o conto Romance Negro, de Rubem Fonseca, a partir do duplo sentido que o autor dá à expressão roman noir, a qual remete, em literatura, seja ao gênero que se desenvolveu no pré-romantismo inglês da segunda metade do século XVIII, seja a um tipo de romance policial americano do século XX chamado de noir. Aproveitando essa dualidade do termo, o autor cria uma narrativa híbrida ao mesclar dois gêneros: o romance gótico e a narrativa policial.

Frenético e melodrama: os vampiros de Polidori e Nodier

Charles Nodier foi um dos grandes responsáveis pela divulgação do romance gótico ou roman noir na França, o qual passou a denominar “frenético”, remetendo ao exagero que caracterizaria esse tipo de literatura. No início do século XIX, no romantismo francês, uma intensa circulação estabelece-se entre o frenético e o melodrama em um intercâmbio de autores, motivos e procedimentos literários. A partir de 1820, o melodrama instala-se no sobrenatural, sobretudo com Le vampire de Nodier, composto em colaboração com Jouffroy e Carmouche; esse melodrama, adaptado do texto de Polidori, The vampire, publicado em 1819, harmoniza-se com o retorno de popularidade por que passa o gothic novel. Essa união do frenético ao melodrama deixa ver duas tendências literárias bastante fecundas no romantismo francês, que se irmanam ainda no sentido em que respondem aos anseios de um público fatigado por séculos de racionalismo e ávido por toda a espécie de sensações e sentimentos.

Janelas mais que indiscretas: Hitchcock e Woolrich em confronto

Considerado una verdadera lección de cine, ya que es una película que se refiere al propio arte cinematográfica, La ventana indiscreta (Rear Window), dirigida por Alfred Hitchcock en 1954, tuvo como base para el guión de John Michael Hayes el cuento “Tenía que ser un asesinato” (“It had to be murder”, 1942), de Cornell Woolrich. Reconocido como uno de los mayores escritores del género policial noir, Woolrich profesaba la “poética del fracaso, [...] conduciendo gradualmente la angustia de la víctima al centro del cuadro, en contraste con la indiferencia mecánica de una sociedad que no se molestaba con su suerte”. (OLIVA, 2003, p.116- 7). La película tuvo un gran éxito de público y crítica, pero esto no había ocurrido con el cuento, que solo se hizo conocido después de su adaptación para el cine. El propósito de este trabajo es realizar un análisis comparativo entre los dos textos, subrayando los siguientes aspectos: 1) la caracterización del género noir (cuando la investigación ya no es un juego para mentes refinadas, como había sido en la narrativa policial clásica) y del suspense (narrativa de tensión que se caracteriza por el aplazamiento de la resolución del enigma), tanto en la narración literaria como en la película; 2) la autorreferencialidad en la película y en el cuento mediante el uso de la metaficción; 3) el problema de la transposición del foco en primera persona de la narrativa para el cine; 4) los diferentes desenlaces, señalando en qué medida indican visiones del mundo también divergentes.

O romance policial contemporâneo pelos caminhos da paródia: uma vertente metalinguística

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)